LED calculator

This is the new version of the single LED series resistance calculator, good for when you have a single LED and need to know "what resistor should I use with my LED?" This calculator determines that for you.

The LED series/parallel array wizard is available for those of you who need to do calculations involving more than one LED. The wizard will help you pick the resistors make the connections for any number of LEDs.

LED calculator: current limiting resistor value

Source voltage
diode forward voltage
diode forward current (mA)

The wizard recommends a 1/8W or greater 560 ohm resistor. The color code for 560 ohms is green blue brown.